The present invention relates to a construction kit for producing lighting-tube systems or three-dimensional frameworks, comprising tubes connected by connecting pieces, wherein the connecting pieces each have at least one tubular extension, and wherein the tubes are divided along axis-parallel surface lines into two interlockable tube shells. The tubes have, at each of their ends a horseshoe-shaped end flange. The end flange is connected to one of the tube shells, and can be pushed in a radial direction onto the tubular extension of the connecting piece. The end flange is also connected to an arcuate closing flange which can be locked with the end flange to form a closed ring surrounding the tubular extension.
A construction kit of this type is known from European Patent No. 0,018,005 of the applicant. The end flange serves, together with the closing flange, to fasten the tube rotatably to the tubular extension of the adjoining connecting piece. The advantage of the horseshoe-shaped design of the end flange is that, when a tube is exchanged in an already-installed three-dimensional framework, the tube shell of a new tube to be inserted, which is connected to the end flanges, can be introduced into the gap in the three-dimensional framework with a purely radial movement. The tube shell can be connected to the tubular extensions by means of the closing flanges, without having to change the position of the adjacent, already-installed tubes.
In a conventional constructional kit, the closing flange can be released completely from the end flange. By means of leaf springs projecting tangentially from the outer periphery at both ends of the closing flange, the conventional closing flange can be locked on inner projections of the tube shell connected to the end flange.
A disadvantage of this conventional construction kit is that the closing flanges can easily be lost and have to be held in a suitable position by hand before being locked on the tube end. The axial position of the closing flanges often has to be corrected once again after locking.
An object of the present invention is to simplify the locking of the closing flanges in the position provided and to ensure that the closing flanges cannot be lost.
This object is achieved according to the present invention, due to the fact that the closing flange is articulated in the form of a hinge to the end flange by means of one arc end.
The closing flange is therefore always connected with the end flange. When assembling the tube, the fitter has both hands free to bring the tube into a suitable position in relation to the adjoining connecting pieces and to push it radially onto the tubular extensions when the closing flanges have been swung open. When the closing flanges are subsequently swung closed and locked, a correct fit of the closing flange is guaranteed because of the hinge-shaped connection to the end flanges.
Further objects, features and advantages of the present invention will become apparent from the detailed description of preferred emobodiments when considered together with the attached figures of drawing.